Novel Therapies for Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema: A Systematic Review of Current Evidence.

BACKGROUND: Angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema can occur at any point during therapy and, when severe, can require mechanical ventilation. Standard agents for anaphylactic reactions have limited efficacy for bradykinin-mediated angioedema and, therefore, agents approved for hereditary angioedema are increasingly prescribed for these patients. OBJECTIVE OF THE REVIEW: This systematic review critically evaluates evidence describing the off-label use of fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), complement 1 esterase inhibitor (C1-INH), icatibant, and ecallantide for treatment of ACEI-induced angioedema. DISCUSSION: A PubMed search was conducted and articles were cross-referenced for additional citations. All full-text clinical trials, case series, and case reports published in the English language describing pharmacologic treatment of ACEI-induced angioedema were included. Thirty-seven publications detailing FFP, PCC, and regimens approved for hereditary angioedema, including icatibant, ecallantide, and C1-INH, are reviewed extensively. CONCLUSIONS: While findings of decreased time to symptom resolution or a cessation in symptom progression have been reported with each of these therapies, additional data showing clinically relevant implications, such as reduced intensive care unit length of stay or avoidance of mechanical ventilation, are warranted, especially when taking cost into consideration. FFP has limited evidence demonstrating a benefit for treatment of ACEI-induced angioedema without consistent dosing strategies. However, given its wide availability and low potential for adverse reactions, FFP therapy may be reasonable. Of the novel agents traditionally used for hereditary angioedema, icatibant has the highest level of evidence and has been reported to be successful in limiting the progression of angioedema.

Angioedema.

OBJECTIVES: Angioedema is a potentially life-threatening occurrence that is encountered by critical care providers. The mechanistic understanding of angioedema syndromes has improved in recent years, and novel medications are available that improve outcomes from these syndromes. This clinically focused review will describe the underlying genetics, pathophysiology, classification and treatment of angioedema syndromes, with an emphasis on the novel pharmacologic agents that have recently become available for acute treatment. DATA SOURCES: A MEDLINE search was conducted with the MeSH terms angioedema, acquired angioedema, hereditary angioedema type III, and angiotensin converting enzyme inhibitor-induced angioedema. STUDY SELECTION: Selected publications describing angioedema, clinical trials, diagnosis, management, and genetics were retrieved (reviews, guidelines, clinical trials, case series), and their bibliographies were also reviewed to identify relevant publications. DATA EXTRACTION: Data from the relevant publications were reviewed, summarized and the information synthesized. DATA SYNTHESIS: The data obtained were used to describe the current state of diagnosis and management of various angioedema syndromes. CONCLUSIONS: Angioedema is a life-threatening syndrome with multiple subtypes, each with a distinct pathophysiology. We present an evidence-based approach to the diagnosis and suggested management of various subtypes of angioedema. Securing the airway remains the most important intervention, followed by administration of both established and more novel pharmacologic interventions based on disease pathology.

Management of Children With Hereditary Angioedema Due to C1 Inhibitor Deficiency.

Hereditary angioedema (HAE) is a potentially life-threatening inherited disease characterized by attacks of skin swelling, severe abdominal pain, and upper airway swelling. Attacks typically begin in childhood, but the appropriate diagnosis is often missed. Attacks do not respond to epinephrine, antihistamines, or glucocorticoids. Recently, many effective drugs have been approved for treatment of adults with HAE, and the Medical Advisory Board of the HAE Patient's Association has developed and reported treatment recommendations for adults. Only 1 medication is approved for treatment of children <12 years of age, and there are no reported consensus recommendations for treatment of young children in the United States. The 11-member Medical Advisory Board, with extensive experience in the treatment of children, in concert with the leaders of the HAE Patient's Association, has developed these consensus recommendations to help in recognition, diagnosis, treatment of attacks, and prophylaxis of children with HAE.

Nanofiltrated C1-esterase-inhibitor in the prophylactic treatment of bradykinin-mediated angioedema.

BACKGROUND: Patients suffering from bradykinin-induced angioedema show recurrent swelling of subcutaneous and submucosal structures. Increased bradykinin levels lead to an increase in vascular permeability and edema formation. Current therapy consists of B2 bradykinin receptor antagonists, C1-esterase-inhibitor (C1-INH) concentrate, or the kallikrein inhibitor ecallantide. In most cases the treatment of acute attacks is sufficient. Prophylactic therapy is recommended only in severe cases. C1-INHc has been shown a safe and efficient option. Its effect on the quality of life has not yet been analyzed. STUDY DESIGN AND METHODS: Patients with inadequate disease control despite an "on-demand therapy" including C1-INHc and/or the B2 receptor antagonist icatibant were switched to long-term prophylaxis consisting in an individual dose of intravenous C1-INHc (Cinryze). None of the patients had been previously treated with ecallantide. Disease-specific quality-of-life questionnaires and patient records were used for evaluation. Disease control, quality of life, adverse events, and administered dosage per month were compared for 6 months on on-demand therapy and the following 6 months under prophylactic therapy. RESULTS: Data of seven patients with hereditary angioedema (HAE) and one patient with acquired angioedema were evaluated. Prophylactic therapy with Cinryze led to a significant and clinically relevant reduction in the overall attack frequency from 6.7 to 2.3 per month without relevant side effects. The frequency of severe attacks was reduced by 89% and quality of life significantly improved. CONCLUSION: Prophylaxis with Cinryze led to a significantly improved quality of life in our cohort of patients with high-frequency bradykinin-induced angioedema attacks that were not sufficiently treated with on-demand medication.

The Janus faces of acquired angioedema: C1-inhibitor deficiency, lymphoproliferation and autoimmunity.

Several clinical and biological features of lymphoproliferative diseases have been associated with an increased risk of developing autoimmune manifestations. Acquired deficiency of C1-inhibitor (C1-INH) (AAE) is a rare syndrome clinically similar to hereditary angioedema (HAE) characterized by local increase in vascular permeability (angioedema) of the skin and the gastrointestinal and oro-pharyngo-laryngeal mucosa. Bradykinin, a potent vasoactive peptide, released from high molecular weight kininogen when it is cleaved by plasma kallikrein (a serine protease controlled by C1-INH), is the mediator of symptoms. In total 46% of AAE patients carry an underlying hematological disorder including monoclonal gammopathy of uncertain significance (MGUS) or B cell malignancies. However, 74% of AAE patients have anti-C1-INH autoantibodies without hematological, clinical or instrumental evidence of lymphoproliferative disease. Unlike HAE patients, AAE patients usually have late-onset symptoms, do not have a family history of angioedema and present variable response to treatment due to the hypercatabolism of C1-INH. Experiments show that C1-INH and/or the classical complement pathway were consumed by the neoplastic lymphatic tissues and/or anti-C1-INH neutralizing autoantibodies. Therapy of AAE follows two directions: 1) prevention/reversal of the symptoms of angioedema; and 2) treatment of the associated disease. Different forms of B cell disorders coexist and/or evolve into each other in AAE and seem to be dominated by an altered control of B cell proliferation, thus AAE represents an example of the strict link between autoimmunity and lymphoproliferation.

Diagnostic and therapeutic management of hereditary angioedema due to C1-inhibitor deficiency: the Italian experience.

PURPOSE OF REVIEW: Hereditary angioedema (HAE) due to C1-inhibitor (C1-INH) deficiency (C1-INH-HAE) is a rare disease, with a reported prevalence of about 1 : 50 000. C1-INH-HAE causes disabling symptoms, which may be life-threatening if swelling affects upper airways. Diagnostic procedures are now well established and the role of bradykinin as the main mediator of plasma outflow eliciting angioedema formation has been clearly elucidated. RECENT FINDINGS: Increased understanding of the pathogenesis of C1-INH-HAE allowed in recent years the development of new drugs targeted to inhibit bradykinin synthesis (Ecallantide) or activity (Icatibant). At the same time, a recombinant C1-INH concentrate (Ruconest) was produced from the milk of transgenic rabbits and two plasma-derived C1-INHs (Berinert, Cinryze) underwent controlled trials to obtain marketing authorization. In 2012, an Italian network for C1-INH-HAE (ITACA) was established by physicians of 17 HAE reference centres to collect data from Italian patients and to homogenize and improve the diagnostic and therapeutic approach to the disease. SUMMARY: Although there is a widespread agreement on therapeutic goals and treatment of C1-INH-HAE acute attacks, different approaches to prophylaxis are still present among HAE experts. The clinical experience of ITACA on a large population of C1-INH-HAE patients followed for several years may help in identifying the most effective strategies for the management of the disease.

Risk of angioedema following invasive or surgical procedures in HAE type I and II--the natural history.

BACKGROUND: Hereditary angioedema (HAE), caused by deficiency in C1-inhibitor (C1-INH), leads to unpredictable edema of subcutaneous tissues with potentially fatal complications. As surgery can be a trigger for edema episodes, current guidelines recommend preoperative prophylaxis with C1-INH or attenuated androgens in patients with HAE undergoing surgery. However, the risk of an HAE attack in patients without prophylaxis has not been quantified. OBJECTIVES: This analysis examined rates of perioperative edema in patients with HAE not receiving prophylaxis. METHODS: This was a retrospective analysis of records of randomly selected patients with HAE type I or II treated at the Frankfurt Comprehensive Care Centre. These were examined for information about surgical procedures and the presence of perioperative angioedema. RESULTS: A total of 331 patients were included; 247 underwent 700 invasive procedures. Of these procedures, 335 were conducted in 144 patients who had not received prophylaxis at the time of surgery. Categories representing significant numbers of procedures were abdominal (n = 113), ENT (n = 71), and gynecological (n = 58) procedures. The rate of documented angioedema without prophylaxis across all procedures was 5.7%; in 24.8% of procedures, the presence of perioperative angioedema could not be excluded, leading to a maximum potential risk of 30.5%. Predictors of perioperative angioedema could not be identified. CONCLUSION: The risk of perioperative angioedema in patients with HAE type I or II without prophylaxis undergoing surgical procedures ranged from 5.7% to 30.5% (CI 3.5-35.7%). The unpredictability of HAE episodes supports current international treatment recommendations to consider short-term prophylaxis for all HAE patients undergoing surgery.

Recent advances in the management of hereditary angioedema.

Hereditary angioedema (HAE) is a rare genetic condition that manifests as painful and potentially life-threatening episodic attacks of cutaneous and submucosal swelling. It results from functional deficiency of C1 inhibitor (C1 INH), which is a regulator of the complement, fibrinolytic, kinin (contact), and coagulation systems. In patients with HAE, the low plasma concentration of functional C1 INH leads to overactivation of the kinin cascade and local release of bradykinin. Bradykinin is responsible for the pain, vascular permeability changes, and edema associated with HAE. Until recently, therapeutic options for HAE have been very limited. Many new therapies have emerged, however, such as C1 INH replacement drugs and medications aimed at components of the contact system (eg, plasma kallikrein inhibitor and bradykinin B2 receptor antagonist). The authors review current and novel treatments for patients with HAE.

HAE update: determining optimal patient specific therapy.

Hereditary angioedema (HAE) is a rare autosomal dominant disease caused by deficient or dysfunctional C1 inhibitor (C1 INH). HAE patients experience recurrent episodes of angioedema affecting the extremities, face, genitalia or submucosal edema in the abdomen or upper airway. Laryngeal attacks can be fatal. The determination of optimal therapy should be based on individualization of patient history and preferences. The parameters include attack frequency, location, severity and burden of illness on quality of life. Patients with HAE need medications for acute attacks; some also require prophylaxis. This is an overview of HAE treatments currently available in the US and how to individualize therapy for patients based on their circumstances. A literature search was performed for HAE and therapeutic modalities currently available. HAE guidelines and randomized, controlled clinical trials were evaluated. There are several options for acute and prophylactic treatment of HAE that have been approved by the Food and Drug Administration. Acute treatments include C1 INH, a replacement therapy; ecallantide, a kallikrein inhibitor; and icatibant, a bradykinin-2 receptor antagonist. Prophylactic treatments include attenuated androgens and C1 INH. These options have been proven safe and effective in clinical trials. Optimal therapy is based on the individual patients need regarding on-demand therapy and/or prophylactic therapy, short-term or long-term. Patients with HAE have individual requirements, based on the nature and frequency of past attacks, occupation, proximity to trained medical personnel, and patient preference. These factors should be used to create a patient-centered approach to management of HAE.

Thrombotic events associated with C1 esterase inhibitor products in patients with hereditary angioedema: investigation from the United States Food and Drug Administration adverse event reporting system database.

STUDY OBJECTIVE: To investigate reports of thrombotic events associated with the use of C1 esterase inhibitor products in patients with hereditary angioedema in the United States. DESIGN: Retrospective data mining analysis. SOURCE: The United States Food and Drug Administration (FDA) adverse event reporting system (AERS) database. MEASUREMENTS AND MAIN RESULTS: Case reports of C1 esterase inhibitor products, thrombotic events, and C1 esterase inhibitor product-associated thrombotic events (i.e., combination cases) were extracted from the AERS database, using the time frames of each respective product's FDA approval date through the second quarter of 2011. Bayesian statistical methodology within the neural network architecture was implemented to identify potential signals of a drug-associated adverse event. A potential signal is generated when the lower limit of the 95% 2-sided confidence interval of the information component, denoted by IC025 , is greater than zero. This suggests that the particular drug-associated adverse event was reported to the database more often than statistically expected from reports available in the database. Ten combination cases of thrombotic events associated with the use of one C1 esterase inhibitor product (Cinryze) were identified in patients with hereditary angioedema. A potential signal demonstrated by an IC025 value greater than zero (IC025 = 2.91) was generated for these combination cases. CONCLUSION: The extracted cases from the AERS indicate continuing reports of thrombotic events associated with the use of one C1 esterase inhibitor product among patients with hereditary angioedema. The AERS is incapable of establishing a causal link and detecting the true frequency of an adverse event associated with a drug; however, potential signals of C1 esterase inhibitor product-associated thrombotic events among patients with hereditary angioedema were identified in the extracted combination cases.

[Several new treatment possibilities of hereditary angio-oedema]. / Flere nye behandlingsmuligheder ved hereditært angioødem.

Hereditary angio-oedema (HAE) is a rare genetic disease caused by deficiency of complement C1 inhibitor. It is characterised by recurrent episodes of subcutaneous or submucosal oedema typically involving the extremities, bowel, face or larynx. Within the latest years it has become evident that the active mediator of HAE attacks is an increased level of bradykinin and various new treatment modalities have been developed. The aim of this paper is to give an update from the Danish HAE Comprehensive Care Centre on current treatment possibilities and address some of the challenges when diagnosing HAE.

Immunotherapy for primary immunodeficiency diseases.

The 2 most commonly encountered primary immunodeficiency syndromes in adult practice are antibody deficiency disorders and hereditary angioedema.Immunologic therapy for these disorders has significantly improved patient management. Therapy with immunoglobulin leads to improvement in overall quality of life. With increasing survival rates and decreasing levels of life-threatening infections in patients with primary antibody deficiencies, disease complications are more commonly encountered. Treatment of these complications with monoclonal antibody therapy seems promising and is likely to increase in the future. More recently,several additional agents have become available, including novel drugs targeted at different elements of the disease process.

Hereditary angioedema (HAE) in children and adolescents--a consensus on therapeutic strategies.

Hereditary angioedema due to C1 inhibitor (C1 esterase inhibitor) deficiency (types I and II HAE-C1-INH) is a rare disease that usually presents during childhood or adolescence with intermittent episodes of potentially life-threatening angioedema. Diagnosis as early as possible is important to avoid ineffective therapies and to properly treat swelling attacks. At a consensus meeting in June 2011, pediatricians and dermatologists from Germany, Austria, and Switzerland reviewed the currently available literature, including published international consensus recommendations for HAE therapy across all age groups. Published recommendations cannot be unconditionally adopted for pediatric patients in German-speaking countries given the current approval status of HAE drugs. This article provides an overview and discusses drugs available for HAE therapy, their approval status, and study results obtained in adult and pediatric patients. Recommendations for developing appropriate treatment strategies in the management of HAE in pediatric patients in German-speaking countries are provided.Conclusion Currently, plasma-derived C1 inhibitor concentrate is considered the best available option for the treatment of acute HAE-C1-INH attacks in pediatric patients in German-speaking countries, as well as for short-term and long-term prophylaxis.

Hereditary angioedema: management of laryngeal attacks.

BACKGROUND: Hereditary angioedema (HAE) patients suffering from laryngeal attacks in the United States faced severely limited treatment options until 2008. These potentially life-threatening episodes occur in over one-half of the patients affected by HAE during their lifetimes. Acute therapy had been relegated to supportive care, intubation, and consideration of fresh frozen plasma (FFP)--the latter with the potential for actually accelerating the speed and severity of the swelling. METHODS: In this article we will review the recently approved and emerging HAE treatments that have evolved from the recognition that bradykinin generation is the fundamental abnormality leading to attacks of angioedema. RESULTS: Acute therapy for laryngeal attacks will be discussed including purified plasma-derived C1 inhibitor (C1INH), recombinant C1INH, an inhibitor of plasma kallikrein (ecallantide), and a B2 receptor antagonist (icatibant). Prophylactic care has also been transformed from a reliance on attenuated androgens with their attendant side effects to C1INH replacement. CONCLUSION: The arrival of these novel therapies promises to transform the future management of HAE.

New treatment options for acute edema attacks caused by hereditary angioedema.

PURPOSE: New treatment options for acute edema attacks caused by hereditary angioedema (HAE) are reviewed. SUMMARY: HAE is characterized by mutations in the C1 inhibitor gene leading to either a reduced expression of C1 inhibitor in the plasma or expression of a functionally impaired C1 inhibitor. HAE is classified into two major types based on the cause of the C1 inhibitor deficiency. Type I HAE is defined by a reduced expression of C1 inhibitor in the plasma, whereas type II HAE is characterized by the expression of a dysfunctional C1 inhibitor protein. Clinical data were reviewed for C1 inhibitor, ecallantide, and icatibant in the treatment of acute edema attacks caused by HAE. C1 inhibitor leads to a faster onset of edema relief and is effective in decreasing the duration of edema. Dosing strategies include fixed dosing and weight-based dosing. Optimal dosing strategies have not been established, but fixed dosing (500-1000 units) or 20 units/kg has been effective in clinical trials and reports. No comparative trials suggest that one strategy is superior to another; however, the approved labeling for acute treatment is based on weight. Ecallantide is also efficacious for treating acute episodes; however, the available evidence is limited to a single published trial. Icatibant has shown variable effects in two trials with placebo and active controls. CONCLUSION: In patients with HAE, most edema episodes only involve the skin and gastrointestinal tract, though airway obstruction caused by laryngeal angioedema is the most common cause of death. I.V. C1 inhibitor should be considered first-line treatment for acute edema attacks because of its fast onset of action and effectiveness, though it is not clear whether fixed or weight-based dosing is preferred. Ecallantide can be considered as a second-line treatment option.

Risk of laryngeal edema and facial swellings after tooth extraction in patients with hereditary angioedema with and without prophylaxis with C1 inhibitor concentrate: a retrospective study.

OBJECTIVE: Tooth extractions may trigger clinical symptoms of hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH). The aim of this study was to determine how many tooth extractions were followed by symptoms of HAE-C1-INH in patients with and without preoperative short-term prophylaxis with C1 inhibitor concentrate. STUDY DESIGN: Tooth extractions and clinical symptoms of HAE-C1-INH were determined from clinical record files of 171 patients with HAE-C1-INH. RESULTS: Facial swelling or potentially life-threatening laryngeal edema, or both, occurred in 124/577 tooth extractions (21.5%) without prophylaxis. Similar symptoms occurred in a fewer proportion of patients undergoing extractions (16/128; 12.5%) after short-term prophylaxis with C1 inhibitor concentrate. The graded dose-response relationship was significant at P < .05. CONCLUSIONS: Short-term prophylaxis with C1 inhibitor concentrate significantly reduces the risk of HAE-C1-INH symptoms after tooth extraction. In some patients, however, facial swellings and laryngeal edema symptoms may occur despite prophylaxis.

When is prophylaxis for hereditary angioedema necessary?

OBJECTIVE: To determine when newer agents, such as C1 esterase inhibitor protein (C1-INH), should be considered as prophylaxis to decrease hereditary angioedema (HAE) attacks as an alternative to androgens, which have significant adverse events. DATA SOURCES: A literature review (PubMed, Google, and Ovid), guideline review, expert panel meeting, and group discussion were performed to decide when prophylaxis is indicated. STUDY SELECTION: Articles addressing HAE therapy published in the peer-reviewed literature were selected. RESULTS: The retrieved studies demonstrate that C1-INH is effective and that the half-life makes it attractive for prophylactic use. The short half-lives of ecallantide, icatibant, and recombinant human C1-INH limit their use as prophylactic agents. Patients with severe anxiety, more than 1 attack per month, rapid progression of attacks, limited access to health care, more than 10 days lost from work or school per year, previous laryngeal swelling, more than 3 emergency department visits per year, more than 1 hospitalization per year, previous intubation, previous intensive care unit care, significant compromise in quality of life, or narcotic dependency should be considered for androgen or C1-INH prophylaxis therapy. CONCLUSION: Patients with HAE with frequent attacks, severe attacks, past laryngeal attacks, excessive loss of work or school, significant anxiety, and poor quality of life should be considered for C1-INH prophylaxis, especially those who fail, are intolerant of, have adverse reactions to, or are not candidates for androgen therapy.